Bronchiectasis

Epidemiology

Pathophysiology

There are several aetiologies of non-CF bronchiectasis, which are categorised below. Generally, the inflammatory response to a severe infection leads to structural damage within the bronchial walls, which causes dilatation. Scarring, which arises as a consequence of the immune response, reduces the number of cilia within the bronchi. This predisposes the individual to further infections.

The causes of bronchiectasis given below are mostly either causative organisms of infection or conditions that place the patient at increased risk of infection.

Post-infectious

A severe infection of the lower respiratory tract can lead to bronchial damage and bronchiectasis. The most typical organisms include:

• Streptococcus pneumonia
• Staphylococcus aureus
• Adenovirus
• Measles
• Influenza virus
• Bordetella pertussis
• Mycobacterium tuberculosis

By TeachMeSeries Ltd (2026)

Fig 1.0: A gram stain of Streptococcus pneumoniae

Immunodeficiency

Primary immunodeficiency accounts for 12–34% of non-cystic fibrosis (CF) bronchiectasis. While up to half of non-CF bronchiectasis cases remain idiopathic. Common immunodeficiency leading to bronchiectasis are:

• Antibody defects: agammaglobulinaemia, common variable immune deficiency or IgA/IgG deficiency
• HIV infection
• Ataxia telangiectasia

Primary ciliary dyskinesia (PCD)

This is an autosomal recessive genetic defect leading to either the reduced efficacy or complete inaction of bronchial cilia. Over 250 different genes are responsible for building the necessary proteins essential for ciliary function. PCD is rare, with an incidence of one in 150,000-300,000 births.

In the chest, this causes problems with mucociliary clearance, leading to increased susceptibility to low-grade infections and irritation from foreign particulates. Figure 2 demonstrates a CT scan of a patient with PCD.

By John S. To, MD (Own work) [Public domain], via Wikimedia Commons

Figure 2: A CT scan of a patient with PCD showing mild bronchial wall thickening

 Post-obstructive

• Foreign body aspiration

Congenital syndromes

• Young’s syndrome: A rare condition associated with bronchiectasis, reduced fertility and rhinosinusitis.
• Yellow-nail syndrome: Another rare syndrome associated with pleural effusions, lymphoedema and dystrophic nails. Bronchiectasis occurs in around 40% of patients.

Clinical Features

History

The key feature that should be elicited from the history is the presence of a chronic, productive cough. Otherwise, there may be no other key symptoms. However, parents/children may complain of:

• Purulent sputum expectoration
• Chest pain
• Wheeze
• Breathlessness on exertion
• Haemoptysis
• Recurrent or persistent infections of the lower respiratory tract

Examination

Physical examination may be entirely normal, but finger clubbing and/or inspiratory crackles may be elicited in children with bronchiectasis. Wheezing can also be heard on auscultation of the chest in some children.

By TeachMeSeries Ltd (2026)

Fig 2.0: An example of finger clubbing

Investigations

The purpose of the investigation of children with suspected bronchiectasis is two-fold. Firstly, the diagnosis needs to be confirmed. Secondly, investigations looking for a cause should be carried out.

Imaging

• Chest X-ray may show bronchial wall thickening or airway dilatation. However, it is important to note that a chest radiograph can appear completely normal in those with bronchiectasis.
• High-resolution CT (HRCT) is the gold-standard investigation to diagnose bronchiectasis. Features indicative of the diagnosis are: bronchial wall thickening, diameter of bronchus larger than that of the accompanying bronchial artery (‘Signet ring’ sign) and visible peripheral bronchi.
• Different patterns seen on HRCT can occur with different aetiologies
  • Bilateral upper lobe bronchiectasis is more common in CF.
  • Unilateral upper lobe bronchiectasis is more common post-TB infection.
  • Focal bronchiectasis (lower lobe) can be seen after foreign body inhalation.

Bronchoscopy

Bronchoscopy is not required to diagnose bronchiectasis and is not routinely performed in all children with the disease. It is generally reserved for children who have evidence of focal bronchiectasis evident on HRCT or when there is evidence of a possible airway abnormality.

Investigating the underlying cause

• A chloride sweat test must be performed to exclude CF. CFTR gene mutation analysis may also be helpful if the sweat test is borderline or there is a strong clinical suspicion of CF.
• Full blood count with leucocyte differential – assess lymphocyte and neutrophil counts.
• Immunoglobulin panel to assess for immunoglobulin deficiency.
• Specific antibody levels to vaccinations, e.g. pneumococcal or Hib (Haemophilus influenzae B) vaccine.
• If bronchoscopy is performed, a ciliary brush biopsy can be taken.
• HIV test

Microbiological assessment

This can be useful in the investigation of children with bronchiectasis as it can indicate the underlying cause, for example, chronic Pseudomonas spp colonisation should prompt investigations for CF. It is important to understand which organisms are isolated in patients. Much like in CF, chronic bacterial infection can lead to declining lung function, and aggressive courses of antibiotics may be needed to treat infection.

Lung function

Spirometry may be completely normal in mild disease. In advanced disease, there can either be an obstructive pattern or a mixed obstructive and restrictive pattern, as severe scarring begins to compromise lung compliance.

Management

The aims of managing children with bronchiectasis are symptomatic relief, preventing progression of lung disease and ensuring normal growth and development.

Chest physiotherapy

Unlike CF, there are no clinical trials that demonstrate the benefit of performing chest physiotherapy in bronchiectasis. However, chest physiotherapy is a mainstay of treatment, and children should see a chest physiotherapist to learn about mucus clearance techniques and should be encouraged to use them.

Exacerbations and antibiotics

• The most commonly isolated organisms include: non-encapsulated Haemophilus influenzae, Streptococcus penumoniae and Moraxella catarrhalis
• Antibiotic regimes depend on the clinical condition – some children will only need short courses at times of infective exacerbations, and in between exacerbations expectorate only a little amount of sputum, whereas others may need more continuous treatment with antibiotics
• Colonisation and infection with Pseudomonas spp. can occur in patients with non-CF bronchiectasis, and in this instance Pseudomonas eradication could be instigated, there is little evidence to show the benefit of this in non-CF bronchiectasis

Other management

• Bronchodilators may be useful in patients who have wheeze. Bronchodilators may also be tried to aid expectoration of sputum prior to commencing chest physiotherapy
• Annual flu vaccine
• Pneumococcal vaccine to protect against pneumonia

Surgery

Surgery is only recommended for bronchiectasis if:

• only affecting a single section of the lung.
• Symptoms are not responding to other treatments
• do not have an underlying condition that could cause bronchiectasis to come back

Follow-up

Children with bronchiectasis should be followed up regularly and should have continual monitoring of their symptoms and lung function.

Complications

The complications of bronchiectasis include:

• Recurrent infection
• Life-threatening haemoptysis
• Lung abscess
• Pneumothorax
• Poor growth and development

Prognosis

The long-term prognosis is entirely dependent on the underlying cause. For example, in patients with post-infective disease, treatment should halt disease progression. In those children with more complex underlying pathology e.g. HIV infection, their prognosis depends heavily on the progression of the causative disease.

References